Designed to mitigate the audible headset noise that can occur in any air band handheld radio.

What is the diameter of the hole for the wire?
This is intended for an aviation headset cord approximately .17" diameter.
Do you have any specs on these ferrite cores? Do you know the mix or frequency range they work at?
If you are getting squealing noise or interference in your headset along with the A6 or A24 then you would use this, by coiling a section of your headset cable to eliminate the noise.